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Objective: Asthma disproportionately impacts and has poorer outcomes in low-income, minority, and inner-city children. The home environment has a profound impact on a child's asthma. Home-based asthma visits have the potential to positively impact a child's asthma, especially in targeted populations. The purpose of this integrative review is 1.) to explore the effectiveness of home-based education and environmental measures and 2.) to explore specific indicators and tools to measure pediatric asthma control and program effectiveness. Data Sources: Medline, CINHAL, and Ovid databases were searched from 2010 to 2017 utilizing the keywords healthy homes AND asthma and home based interventions AND asthma. Study Selections: A total of 71 articles were retrieved of which 27 articles met the inclusion criteria of English language, human subjects, and the inclusion of pediatric populations. Three additional articles were hand-searched from previous references. In total, 30 articles were reviewed. A quality appraisal was conducted utilizing standardized appraisal tools. Results: Home-based asthma education and environmental interventions have proven to be effective. The programs reviewed varied in types of interventions, intensity and duration, the type of provider, length of follow-up, and outcome measures. Successful programs were patient-centered, included a home assessment and individualized education and interventions, and were collaborative. Multiple outcome indicators such as health care utilization, asthma control, missed days of school or productivity, asthma symptoms, and verification of environmental remediation have been utilized. Conclusion: Home-based asthma programs can be beneficial to children with poorly controlled asthma and have the potential to be cost-effective.  相似文献   
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Morphine (8–100 mg/kg IP) induces place preference conditioning in mice. The effect of two different periods of isolation (15 and 30 days) was examined. Mice isolated for 15 days but not 30 days exhibited place preference conditioning to morphine (8 mg/kg). After 30 days of isolation morphine could not induce place preference conditioning with the following doses (8, 16, 64, 100 mg/kg). Social regrouping of male mice previously isolated for 30 days with naive female mice for 15 or 30 days resulted in a reappearance of the conditioned place preference to morphine (16 mg/kg). The specificity of this associative deficit was examined by testing learning in isolated compared to non-isolated mice in two distinct settings: escape learning in the Morris water maze and passive avoidance acquisition and retention. On the Morris water maze isolated mice did not differ from non-isolated mice regarding place learning, the probe trial or extinction. Isolated mice were unimpaired in passive avoidance acquisition and retention. It was concluded that the deficits in place preference conditioning were not the result of a global learning impairment in isolated mice. Received: 10 April 1996 /Final version: 20 September 1996  相似文献   
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 Lactate/H+ transport kinetics were determined by means of the pH-sensitive probe BCECF in sarcolemmal giant vesicles, obtained from rat skeletal muscle, and related to variations in lactate/H+ transport capacity. Vesicle preparations were made from red and white muscles, mixed muscles, denervated muscles, muscles of old rats and rats that had been subjected to high-intensity training, endurance training, repeated exposure to hypoxia, and hypothyroid or hyperthyroid treatments. The lactate/H+ transport capacity of red muscles was greater than that of white muscles, and this difference was associated with a higher maximal transport rate (V max) in red muscles, whereas the K m was similar in the two muscle types. High-intensity training and hyperthyroidism increased the lactate/H+ transport capacity by enhancing V max without affecting K m. Similarly, a reduced transport capacity with old age and hypothyroidism was due to a decrease in V max. The denervation-induced decline in lactate/H+ transport capacity resulted from both an increased K m and a reduced V max. The present data show that muscle type differences and most changes in the lactate/H+ transport capacity are mediated by modifications in V max, which is expected to represent the number of membrane transporter molecules. K m is unaffected by most treatments and appears to be independent of fibre type. Received: 10 February 1998 / Received after revision: 21 April 1998 / Accepted: 24 April 1998  相似文献   
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Since there is strong evidence of a preferential LDL accumulation in tumor cells, LDL might be of interest for tumor imaging. We have tested the ability of 99mTc-LDL in tumor imaging with B16-melanoma-bearing mice as a model for further applications in human studies. The LDL fixation rate was higher with 99mTc-labeled LDL than with 125I labeled LDL. Since technetium-99m remains trapped in the cells, 99mTc-LDL is a well-adapted radioligand because of information given by this radiotracer on the receptor metabolism. We observed that, at early growth stages, the tumor took up the LDL at a maximal rate, suggesting differences in cholesterol metabolism as a function of tumor growth. Accumulation of label in the tumor area was perfectly observable in tumor-bearing mice on scintigraphic images. Computerized quantification of the regions of interest (as well as biodistribution studies including killing of the animals) showed a 1.81 -fold increase in uptake by the tumor as compared to the liver and a 28-fold increase as compared with corresponding normal tissue (muscle of the left leg) at day 8 of tumor growth. These data give strong support to the value of this non-invasive method in visualizing and quantifying the tissue LDL uptake in vivo, including the precise information provided by nuclear scintigraphy on the distribution of the radiolabeled LDL in the different tissues. 99mTc-LDL could be an efficient tool for further diagnostic or therapeutic exploration in cancer patients.  相似文献   
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CASE REPORT: The reported female patient underwent sub-total resection of an intra-medullary cervicothoracic astrocytoma classified as WHO grade II in 1984 at the age of 18 months and received local irradiation. In 1989, a local recurrence was diagnosed and a partial resection was performed. Sixteen years later, a small recurrent cervicothoracic tumour was found and spinal seeding to the equine nerve roots and the left cerebellar cortex was apparent on MRI. The patient was implanted with a ventriculoperitoneal shunt for a pseudo-tumour cerebri producing papilloedema, which eventually lead to amaurosis. After an extended biopsy, the invasive lumbosacral tumour was classified as glioblastoma multiforme. Two months later, the patient died after rapid progression of the caudal cranial nerve dysfunction. DISCUSSION AND CONCLUSION: Anaplastic progression and dissemination of spinal astrocytomas even two decades after initial diagnosis and treatment are rare. Therapies and diagnostic follow-up strategies are discussed.  相似文献   
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Using Rbp4-null mice as models, we have established for the first time the kinetics of the spermatogenetic alterations during vitamin A deficiency (VAD). Our data demonstrate that the VAD-induced testicular degeneration arises through the normal maturation of germ cells in a context of spermatogonia differentiation arrest. They indicate that retinoic acid (RA) appears dispensable for the transition of premeiotic to meiotic spermatocytes, meiosis, and spermiogenesis. They confirm that RA plays critical roles in controlling spermatogonia differentiation, spermatid adhesion to Sertoli cells, and spermiation, and suggest that the VAD-induced arrest of spermatogonia differentiation results from simultaneous blocks in RA-dependent events mediated by RA receptor gamma (RARgamma) in spermatogonia and by RARalpha in Sertoli cells. They also provide evidence that expression of major RA-metabolizing enzymes is increased in mouse Sertoli cells upon VAD and that vitamin A-deficient A spermatogonia differ from their RA-sufficient counterparts by the expression of the Stra8 gene.  相似文献   
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